Trail mixes have become popular as nutritious and convenient snacks for an increasingly health conscious consumer. These mixes typically contain nuts and dried fruit in combination with other food particulates (e.g., seeds, chocolate, carob, yogurt, sugars, etc.). Trail mixes typically contain not more than about 20% moisture, more typically from about 5 to 15% moisture. This low moisture characteristic helps to maintain the microbial and to some extent the chemical stability of trail mix products. Accordingly, such low moisture characteristics help provide for a product with a commercially viable shelf life.
Trail mixes containing dried fruits and nuts, however, are often described as having undesirable textural characteristics. In particular, the dried fruits in such mixes normally have a tough fibrous texture due to their low moisture content. The nuts in such mixes often have a rubbery texture which lacks sufficient crunchiness. This rubbery texture is due primarily to the excess moisture that has migrated into the nuts from the surrounding dried fruit.
There have been a few attempts to improve the texture of trail mixes containing nuts and dried fruit. One such attempt is to mix raw or freshly roasted nuts with intermediate moisture fruit. Immediately after mixing, the nuts have a crunchy texture while the intermediate moisture fruits have a tender texture. Over several days, however, the intermediate moisture fruit loses moisture to the nuts. The texture of the fruit soon becomes tough and fibrous as the texture of the nuts becomes rubbery.
Another attempt to improve the texture of dried fruit products is to infuse dried fruit with humectants. This approach is commonly used to make fruit-containing breakfast cereals. The infused humectants decrease the water activity of the fruits thereby inhibiting moisture migration from the dried fruit to any surrounding drier material (e.g., cereal flakes) since the humectant binds the water in the fruit. Moreover, the infused fruit can contain even more moisture which results in a more tender fruit texture. Humectants commonly used in dried fruit include sugars (e.g., dextrose, sucrose) and polyhydric alcohols (e.g., glycerol, sorbitol, mannitol). However, the use of such humectants in high concentrations in trail mix products is not desirable. High concentrations of humectants, especially polyhydric alcohols, can cause a throat burning sensation when used at sufficient concentrations. This sensation is not readily apparent in breakfast cereals where only small amounts of infused fruit are used and any burning sensation is masked by the use of milk on the breakfast cereal. Of course, trail mixes are not commonly used with milk and they typically contain much more fruit than breakfast cereals. The use of high concentrations of humectants also tends to mask the natural flavor of the dried fruit by contributing artificial, excessively sweet, or off flavors.
Another attempt to improve the texture of dried fruit products is to coat or dust the dried fruit with moisture binders such as finely ground modified or native starches, pregelatinized starches, cellulosics, modified cellulosics and like materials. The fruit surface can also be dusted with crystalline solids such as maltose, lactose, dextrose and sucrose. While these moisture binders help to retain the moisture in the dried fruit, their ability to do so is very limited. Consequently, they are not commonly relied upon as the sole means for retaining moisture within dried fruit.
Accordingly, there is a continuing need to provide trail mix products which have improved texture and texture stability. Specifically, there is a need to provide fruit and nut mixes wherein the fruits are tender, the nuts are crunchy, and these textural characteristics remain for prolonged periods at ambient temperatures.